What's the difference between dermatology cosmetics and cosmetics? Is there a difference?

I've been paying a bit more attention to my skin lately, and it suddenly occurred to me,

What's the difference between dermatologist-recommended cosmetics and regular drugstore cosmetics?

There was a huge price difference; are the ingredients really that different?

Whenever I go to a dermatologist, they always recommend their own cosmetics.

Is that because it's really effective?

Or is it just because of something like a partnership?

Has anyone tried dermatologist-recommended cosmetics?

Do you definitely feel a difference when using dermatologist-recommended cosmetics?

Am I such a question mark killer lol. I'm genuinely curious 😭